Although economic agents should discern signals from noise when drawing from experience, recent evidence suggests decision-making can be based on both noise and signal components. This column uses a natural experiment of IPO lotteries in India to show that randomised gains cause winning investors to increase applications to future IPOs and substantially increase portfolio trading volume in non-IPO stocks relative to lottery losers. Investors appear to draw inferences about their skill from noise.

Economists have traditionally viewed healthcare as a luxury good – consumption of it will increase more than proportionally as income rises. This column challenges this view, exploiting the windfall of lottery winnings to estimate elasticities for healthcare demand in the UK. Results suggest that income elasticities for public healthcare services are close to zero. A medium to large windfall is found instead to increase the uptake of private health insurance and preventative services. This suggests that rising incomes will increase private sector demand, but will leave public healthcare demand unchanged.

Are lotteries more efficient than voluntary contributions in funding public goods? The authors of CEPR DP8319 argue that they can be, as long as the lottery proceeds go to worthy causes that induce 'warm glow' altruistic preferences in lottery players.